I'm running two 580s in sli. I use two 27inch monitors at 1920 x 1080 the gpu temps i get when using both monitors are 65 - 67c (top) and 40 - 42c (bottom) idle. When only using one monitor the temps are 45 - 46c (top) and 39 - 40c (bottom) idle. My computer case is the 800d http://www.newegg.com/Product/Product.aspx?Item=N82E16811139001&Tpk=800d I have 3 fans up top sucking out the hot air while 1 fan at the bottom blowing in air. I have two extra fans i could use but not sure where to put it.